Devices for fastening an airbag unit in a subassembly of a motor vehicle are known. For example, an airbag module in which the airbag unit has on its outside elastically deformable snap-in hooks which can engage behind latching sections on the inside of the lateral wall of the airbag housing is known from EP 1 314 621 A1. In this case, the airbag unit is introduced into the airbag housing from above. As soon as the snap-in hooks reach the region of the latching sections, the snap-in hooks slide along the latching sections, being deformed elastically in the direction of the lateral wall of the airbag unit. Upon reaching the end position of the airbag unit in the airbag housing, the snap-in hooks spring back and engage below the latching sections of the airbag housing. The airbag module is thereby fixed in the airbag housing. This device has the disadvantage that the subassembly to which the airbag unit is to be snap-fastened must have a lateral wall on which the latching sections can be arranged. It is not possible to connect the airbag unit to a flat plate.
A device for snap-fastening an airbag unit in an airbag housing is further known from U.S. Pat. No. 5,620,201. In this device the airbag unit has a snap-in mechanism on each opposite side. This snap-in mechanism has a housing in which is mounted a spring-loaded pin which, during installation of the airbag unit, is pressed back against the spring force by the respective lateral wall of the airbag housing and slides along the inner wall of the airbag housing until it is pressed by the spring into an opening of the airbag housing,
whereby the airbag unit is locked to the airbag housing. Locking to a motor vehicle subassembly which does not have lateral walls is also possible. In this case, an angled portion which has a perpendicular section replacing the lateral wall must be mounted on the subassembly for each snap-in mechanism. In the case of this device, too, therefore, a lateral wall or a corresponding substitute must be provided in order to fix the airbag unit.